Stokers can be used to feed a fuel such as coal or biomass to and/or through a furnace for combustion on a traveling grate in an interior area of the furnace. Combustion of the fuel creates heat, pressure and combustion byproducts such as ash in the interior area of the furnace. The stokers generally include a stationary base secured to the floor beneath the furnace. Typical stokers include a seal defined by a sealing portion of the base which sealingly engages a plurality of plates that move with the traveling grate, for example on a chain conveyor system. The purpose of the seal is to ensure that a proper amount of air passes into the furnace to aid in the combustion of the fuel on the plurality of plates. Improper amounts of air can cause non-uniform combustion of the fuel and create hot spots, causing deterioration and premature failure of the plurality of plates that move with the traveling grate.
Moreover, the seal is subject to mechanical wear because the plates move relative to the sealing portion of the base. In addition, the combustion byproducts are typically abrasive and can migrate into the seal. The abrasiveness of the combustion byproducts can accelerate wear of the seal, which will increase the gap through which an improper amount of combustion air can enter the furnace.